Brown University Sunil Tripathi has been missing since March 16. / Brown University

by Alia E. Dastagir, @alia_e USA TODAY

by Alia E. Dastagir, @alia_e USA TODAY

The FBI has joined the search for a possibly suicidal Brown University student who has been missing from his Providence, R.I., apartment for more than a week, The Providence Journal reported on Sunday.

Sunil Tripathi, 22, was on approved leave from the Ivy League school, according to a public Facebook page set up by his family.

"Sunil has been struggling with depression since he took a leave of absence from Brown last year," the Facebook page stated. "A note suggestive of suicidal intent left behind in his apartment has his family extremely worried."

Tripathi was last seen on campus on the morning of March 16, according to a statement from the university. His cell phone and wallet were found in the apartment, CNN reported. Tripathi's bicycle -- his main form of transportation -- was also found in the apartment he shared with other students, his sister, Sangeeta Tripathi, told ABC News.

"Between family and friends, we are in constant contact with him," Tripathi, 30, told ABC. "We became worried when he didn't respond to many missed calls."

Brown is encouraging the community to join in the search, which is being lead by the Providence Police Department.

"Our concerns are first and foremost with Sunil and his family," Margaret Klawunn, vice president for student life and campus services, said in a statement. "We are hopeful that by encouraging the Brown community to help spread the word that Sunil will be located."

Tripathi grew up in Bryn Mawr, Pa., and has been living in Providence since 2008. His sister told ABC News that he is the youngest of three siblings, who have all attended Brown. He is a philosophy major and a talented saxophonist.

Tripathi was last seen wearing blue jeans, a black Eastern Mountain Sports ski jacket, glasses, and a Philadelphia Eagles wool hat. He is six feet tall and weighs 130 pounds.

The university said the search has expanded outside of Providence to include Boston, Connecticut, New York, and Philadelphia.

"Every minute is (like) 10 years," Sungeeta told the New York Daily News, who has been searching for her brother since the family arrived in Providence on March 17. "We can't imagine leaving without knowing he's OK."